Production of filaments and the like



Patented Oct. 20, 1936 UNETED STATES PRODUCTION OF FILAMENTS AND THELIKE Henry Dreyfus, London, England No Drawing. Application August 22,1932, Serial 16 Claims.

This invention relates to the manufacture of artificial filaments,threads, yarns, ribbons, films or the like of reduced, subdued ormodified lustre, and is especially valuable for the production of suchmaterials having a basis of cellulose acetate or other cellulose estersor ethers. The invention also includes fibres or other materials madefrom or containing such products.

The manufacture of artificial filaments and like products having subduedlustre has recently become of great importance. In most cases thesubduing of the lustre has been achieved by incorporating in thespinning solutions used in the manufacture of the materials finelydivided powders, and particularly finely powdered pigments, which areworked up with the solvent or with part of the spinning solution beforebeing incorporated. in the main bulk of the spinning solution. While theincorporation of these powders, 20 and especially pigments, in thematerials leaves little to be desired in the matter of lustre,nevertheless the artificial filaments and other products containing suchbodies have disadvantages, the most notable being that they tend to cutthe guides which are used either on the spinning machine itself or inthe textile processing of the filaments up to the time when they areWoven or knitted into fabrics.

I have now found that the required subduing of the lustre can beproduced quite eificiently, and at the same time the materials of lowlustre have less tendency to cut the guides, by the use of substanceswhich in the solid state are colloidal in character. According to theinvention such substances are incorporated'in the spinning solutions insuitable proportions for securing the desired degree of delustring, thespinning solutions being then spun by dry or wet spinning methods.

The substances which are to be used in accordance with the presentinvention are in general those which are precipitated from aqueous mediain a'gelatinous or flocculent form, and the term colloidal is used inthis specification in this sense, and not as connoting a particularparticle size in the spinning solution. Examples of suitable substancesare precipitated oxides, hydroxides or hydrated oxides of titanium,aluminium, zinc and tin. The hydrated oxides used may be those which aretermed, for example, orthoor meta-titanic acids and meta-stannic acid.Other suitable colloidal substances are for example the basic zinccarbonates, and the phosphates, silicates, tungstates, borates,silico-tungstates, tungsto-borates and phospho-tungstates which areinsoluble in water, and notably those of the alkaline In Great BritainSeptember 16,

earth metals, for example calcium, barium or magnesium, and also ofaluminium, zinc, tin, lead and titanium.

The colloidal bodies may be reduced to the necessary finely dividedstate for passage through 5 the spinning nozzles and may be incorporatedin the spinning solutions by any suitable methods. I prefer to employthe compounds in the form in which they are precipitated from aqueoussolutiOns of soluble salts or compounds. In this form they exist asgelatinous or flocculent masses permeated with a large mass of water. Inorder to incorporate them in the spinning solution, these aqueousjellies may, for example, be worked with acetone or other suitablesolvent used for making 15 up the spinning solution, or with a smallproportion of the spinning solution itself, and the whole thenincorporated in the spinning solution, or the aqueous jelly with orwithout working with acetone or other solvent may be worked with thecellulose acetate or other bases used for manufacturing the spinningsolution before the spinning solution is actually made up. If desired, acolloidal solution of the substance may be mixed with a solution of thecellulose acetate or other base, and the whole precipitated to form aconvenient complex for making up the spinning solution. Such solutionmay, in the case of organic derivatives of cellulose, be either theesterification or etherification solution itself, or a solution formedby dissolving the cellulose derivative in a suitable solvent.

In most cases it is not necessary to grind the product beforeincorporating it with the solvent or base of the spinning solution, thenecessary subdivision being capable of attainment during the actualprocess of working. However, if preliminary grinding is resorted to, itis preferable that the solid material should not be dried during anypart of this process. It may, for instance, be ground in the presence ofthe water which is already contained in it or in the presence of excesswater. Another method which is suitable for use in accordance with theinvention consists in causing the reagents which are adapted to yieldthe colloidal product to react in the presence of the cellulose acetateor other base used for making up the spinning solution, or in thespinning solution itself. Thus, for example, in the case of employingcellulose acetate as base it is common practice to employ as a solventan acetone containing 5% or even more of water, and in fact the additionof such Water to the spinning solution enables the filaments to be drawndown much more readily to fine denie-rs.

This added water may be the means of introducing into the spinningsolution reagents necessary for the formation therein of the colloidalbody. Thus, for instance, cellulose acetate may be dissolved to thedesired concentration in anhydrous acetone or acetone containing onlylittle water, one of the reagents dissolved in water added andthoroughly mixed therewith, and then the other reagent also dissolved inwater may be added thereto, and the whole mixed thoroughly. In thismanner a very uniform incorporation of the colloidal body is achieved. Asimilar formation of the colloidal body in the presence of the celluloseacetate may be effected by mixing the reagents in the presence of anyother suitable solution of the cellulose acetate and subsequentlyprecipitating the complex of cellulose acetate and colloidal body. Thismay then be dissolved in acetone or other desired solvents.

As a further alternative where feasible the reagents necessary for theformation of the colloidal body may be dissolved in organic solvents,and in this form caused to react, for eX- ample, in the spinningsolution itself, or in the presence of the cellulose acetate or otherbase. In the case of viscose or like aqueous spinning solutions theformation of the colloidal body 7 in the midst of the spinning solutionmay take place in a normal manner by reaction of the reagents dissolvedin the aqueous reagents.

Either during the working of the colloidal body with the spinningsolution or with the constituents thereof, or during a preliminarygrinding, the colloidal body is, if necessary, reduced to the requiredstate of sub-division to enable it to pass the spinning nozzles in thespinning of artificial filaments of commercial deniers. It is usuallysufficient to attain a particle size of somewhat less than 0.003 mm.,but if desired the average particle size may be reduced to 0.0001 to0.0005 mm.

If desired, together with the colloidal body other reagents, andespecially reagents adapted to assist the dispersion of the colloidalbody in the spinning solution, may be added, for example Turkey red oil,preferably applied in relatively small proportions, or other oils, asfor example oleic acid, linseed oil, olive oil, White petroleum oil andthe like.

The following examples illustrate the invention but it is to beunderstood that they do not limit it in any way.

Example 1 A fairly concentrated solution containing about 210 parts byweight of Al(NO3)3 is added to a solution of about 130 parts by weightof NaOI-I, the aqueous suspension of Al(OH) 3 heated to boiling for ashort time and the precipi tate then filtered 01f and washed free fromsoluble salts. The mass of aluminium hydroxide is then worked up withacetone and incorporated in a spinning solution of cellulose acetate inacetone, or it may, if desired, be worked up with a portion of thespinning-solution or with, the cellulose acetate itself.

Example 2 A solution containing about 1% by weight of zinc nitrate ispoured at room temperature into an equivalent solution of sodiumcarbonate also of about 1% concentration with good stirring. Theprecipitate is well Washed with water, and may then be incorporated in aspinning solution as described in Example 1.

As previously indicated, the spinning solutions prepared as describedabove may be spun by dry or Wet spinning processes.

The invention may be applied to'the manufacture of dulled filaments orother products from viscose or other aqueous solutions, but is mostvaluable in its application to the spinning of solutions of celluloseacetate or other cellulose esters or ethers, for example celluloseformate, cellulose propionate, cellulose butyrate, cellulosenitroacetate or other organic esters of cellulose, cellulose nitrate, orcellulose ethers, e. g. ethyl or benzyl cellulose, or mixedether-esters. Where, in the accompanying description reference is madeto substances in a colloidal form, it is to be understood that the termimplies only substances which are in a gelatinous or fiocculent form.

What I claim and desire to secure by Letters Patent is:

1. Process for the manufacture of artificial fila ments, threads, yarns,ribbons, films and the like having a modified lustre, which comprisesforming the said products from spinning solutions containing aninsoluble inorganic substance in a gelatinous or fiocculent form.

2. Process for the manufacture of artificial filaments, threads, yarns,ribbons, films and the like containing cellulose acetate and having amodified lustre, which comprises forming the said products fromsolutions of cellulose acetate, which solutions contain a substantiallywhite insoluble inorganic substance in a gelatinous or fiocculent form.

3. Process for the manufacture of artificial filaments, threads, yarns,ribbons, films and the like containing cellulose acetate and having amodified lustre, which comprises incorporating in solutions of celluloseacetate a substantially white insoluble inorganic substance in agelatinous or fiocculent form permeated with water, prepared, prior toits incorporation, by precipitation from aqueous media, and forming thesaid products from the resulting solutions.

4. Process for the'manufacture of artificial filaments, threads, yarns,ribbons, films and the like containing cellulose acetate and having amodified lustre, which comprises forming the said products fromsolutions of cellulose acetate, which solutions contain aluminumhydroxide in a gelatinous or fiocculent form permeated with water, thesaid aluminum hydroxide being formed by precipitation from aqueous mediaprior to it incorporation into the solutions.

5. Process for the manufacture of artificial filaments, threads, yarns,ribbons, films and the like containing cellulose acetate and having amodified lustre, which comprises forming the said products fromsolutions of cellulose acetate, which solutions contain basic zinccarbonate in agelatinous or fiocculent form permeated with water, andsaid basic zinc carbonate being formed by precipitation from aqueousmedia prior to its incorporation into the solutions.

6. Process for the manufacture of artificial filaments, threads, yarns,ribbons, films and the like containing cellulose acetate and having amodified lustre, which comprises forming the said' '7. Process for themanufacture of artificial fila ments, threads, yarns, ribbons, films andthe like containing cellulose acetate and having a modified lustre,which comprises forming the said products from solutions of celluloseacetategwhich solutions contain, in a gelatinous or fiocculent form,barium tungstate.

8. Process for the manufacture of artificial filaments, threads, yarns,ribbons, films and the like containing cellulose acetate and having amodified lustre, which comprises forming the said products fromsolutions of cellulose acetate, which solutions contain barium tungstatein a gelatinous or flocculent form permeated with water, the saidtungstate being formed by precipitation from aqueous media prior to itsincorporation.

9. Artificial filaments, threads, yarns, ribbons, films and the likehaving a modified lustre, which contain particles of an inorganicsubstance in a gelatinous or fiocculent form.

10. Artificial filaments, threads, yarns, ribbons, films and the likecontaining cellulose acetate and having a modified lustre, which containparticles of a substantially white insoluble inorganic substance in agelatinous or fiocculent form.

11. Artificial filaments, threads, yarns, ribbons, films and the likecontaining cellulose acetate and having a modified lustre, which containparticles of aluminum hydroxide in a gelatinous or fiocculent form, theparticle size of the aluminum hydroxide being between 0.003 and 0.0005mm.

12. Artificial filaments, threads, yarns, ribbons,

films and the like containing cellulose acetate and having a modifiedlustre, which contain particles of basic zinc carbonate in a gelatinousor flocculent form, the particle size of the basic zinc carbonate beingbetween 0.0001 and 0.0005 mm.

13. Artificial filaments, threads, yarns, ribbons, films and the likecontaining cellulose acetate and having a modified lustre, which containparticles of a tungstate of an alkaline earth metal in a gelatinous orfiocculent form, the particle size of the tungstate of the akaline earthmetal being between 0.003 and 0.0005 mm.

14. Artificial filaments, threads, yarns, ribbons, films and the likecontaining cellulose acetate and having a modified lustre, which containparticles of barium tungstate in a gelatinous or fiocculent form.

15. In a process for the manufacture of artificial filaments, threads,yarns, ribbons, films and. the like having a modified lustre, the stepsof forming a solution of a suitable base and containing a finely dividedinsoluble substantially white inorganic substance in a gelatinous orflocculent form distributed throughout the solution and extruding thesolution through suitable orifices into a setting medium.

16. Solutions for the manufacture of artificial filaments, threads,yarns, ribbons, films and the like having a modified lustre whichcomprise a finely divided insoluble inorganic substance in a gelatinousor flocculent form distributed through out a solution of an organicderivative of cellulose.

HENRY DREY'FUS.

